Embodiments of the present innovation generally relates to the field of medical imaging and more specifically relates to enhanced imaging of subsurface blood vessels or other structures of interest that differentially scatter or reflect specific wavelengths of light as compared to tissues that surround these structures.
Various medical procedures require a physician or technician to discern the location of blood vessels (generally called vasculature herein) embedded in bodily tissues and generally covered with one or more layers of translucent or diffuse tissue (for example, skin). The requirement to “find the vein” can be a positive requirement, as is the case for phlebotomy, or it can be a negative requirement, as when the issue is patient safety. For example, the carotid artery is located immediately adjacent to the pharynx and esophagus. If this artery were inadvertently damaged during a procedure in the throat, the consequences for the patient could be dire.
Furthermore, some of these medical procedures are applied inside various bodily orifices, for example the throat. Often, the physician or technician (referred to herein more generally as the “operator”), must rely on an imaging system to see what he or she is doing in these constricted spaces. While some procedures may be performed with direct view imaging systems (that is, imaging systems that use some form of optical relay elements to present a live image to the operator) there has been a general trend to replace these combinations of lens, mirrors, optical fibers, etc with electronic imaging systems, specifically with miniature video cameras connected to electronic displays. Some electronic imaging systems include optical relay systems in which the operator's eye(s) have been replaced by miniature video cameras. More recently, the original, relatively bulky, black and white video cameras have been replaced by miniaturized, full color and/or higher resolution video cameras, said cameras often located in close proximity to the tissue being examined, thereby eliminating most of the elements in the optical relay systems.
When cutting tissue during surgery of the human body or animals, inadvertent damage to vasculature must be avoided. In open surgery, surgeons have a variety of ways of avoiding vasculature, including palpation, gentle proving with instruments, careful dissection, and direct stereoscopic (human) vision (magnified or unaided) to determine tissue topography and/or pulsatile movement of vasculature. However, many open surgeries have been replaced by minimally invasive surgery (MIS) techniques. MIS techniques include percutaneous procedures of the abdomen (laparoscopy), percutaneous procedures of the thorax (thoracoscopy), natural orifice surgery (NOS, e.g., upper gastrointestinal endoscopic surgery, colonoscopic resections), and natural orifice transluminal endoscopic surgery (NOTES, e.g. trans-gastric appendectomy). In many of these MIS procedures, direct palpation is not possible, probing/dissection with instruments is limited, and 3-D vision is generally not available.
Robotic surgery (RS) is also being adopted for a variety of procedures. The same issues relating to inadvertent damage to vasculature apply to robotic procedures, though 3-D optical imaging is more commonly available in surgical robots.
There is an unmet need for an imaging apparatus and related methods of use that will help surgeons avoid inadvertent damage to vasculature during operative procedures in general and during MIS and RS procedures in particular. The imaging apparatus must be substantially real-time (e.g., having a delay shorter than a typical human's ability to detect) and ideally does not compromise the quality of the surgical visualization. Preferably the apparatus can be integrated into instruments without unduly increasing the size of the instruments or introducing any new hazard to patient or user.